Halogenated Nitro- Compounds

I itro-DisplacementPolymerization. The facile nucleophilic displacement of a nitro group on a phthalimide by an oxyanion has been used to prepare polyetherimides by heating bisphenoxides with bisnitrophthalimides (91). For example with 4,4 -dinitro monomers, a polymer with the Ultem backbone is prepared as follows (92). Because of the high reactivity of the nitro phthalimides, the polymerkation can be carried out at temperatures below 75°C. Relative reactivities are nitro compounds over halogens, Ai-aryl imides over A/-alkyl imides, and 3-substituents over 4-substituents. Solvents are usually dipolar aprotic Hquids such as dimethyl sulfoxide, and sometimes an aromatic Hquid is used, in addition. 

Nitro-compounds have often a yellow or red colour, are with difficulty or not at all volatile, possess a much higher boiling-point than the corresponding halogen derivatives, and are denser than water, and insoluble in that liquid. 

Since various substituents are tolerated, the Friedlander reaction is of preparative value for the synthesis of a large variety of quinoline derivatives. The benzene ring may bear for example alkyl, alkoxy, nitro or halogen substituents. Substituents R, R and R" also are variable. The reaction can be carried out with various carbonyl compounds, that contain an enolizable a-methylene group. The reactivity of that group is an important factor for a successful reaction. 

Nitromethane has been used as a solvent for molecular bromination297. The bromination of polymethylbenzenes in nitromethane, acetic acid, and 1 1 mixtures of these solvents at 30 °C, showed that rates were much faster (about 330-fold) in nitromethane than in acetic acid. With nitromethane, in the bromine concentration range 0.01-0.02 M, the reaction was third-order in bromine. The relative deactivating effects of m-halogen substituents were measured in terms of the time taken for 10 % reaction to occur, and these values are given in Table 71 from which the relative reactivities in the different solvents are apparent the deactivating effects of the m-nitro substituent were obtained by comparison with the reactivity of chloromesitylene at different concentrations (0.035, 0.055 M) of reactants. The results for the nitro compounds were interpreted in the same way... 

Coulometry. Even in water, controlled potential or potentiostatic coulometry is a difficult and often time-consuming technique, as the analyte must participate in a direct electrode reaction. Therefore, in non-aqueous media there are only a few examples of its application, e.g., the potentiostatic coulometry of nitro and halogen compounds in methanol (99%) with graphical end-point prediction, as described by Ehlers and Sease153. 

Competitive consecutive reactions are combinations of parallel and series reactions that include processes such as multiple halogenation and nitration reactions. For example, when a nitrating mixture of HN03 and H2S04 acts on an aromatic compound like benzene, N02 groups substitute for hydrogen atoms in the ring to form mono-, di-, and tri-substituted nitro compounds. 

A sample exploded on vacuum distillation at 60° C, though not at 40°C/33 mbar. See Other A-HALOGEN COMPOUNDS, A-NITRO COMPOUNDS... 

Tellurium Tetrahydrofuran Tetranitroaniline Tetranitromethane Thiocyanates Thionyl chloride Thiophene Thymol Halogens, metals Tetrahydridoaluminates, KOH, NaOH Reducing materials Aluminum, cotton, aromatic nitro compounds, hydrocarbons, cotton, toluene Chlorates, nitric acid, peroxides Ammonia, dimethylsulfoxide, linseed oil, quinoline, sodium Nitric acid Acetanilide, antipyrine, camphor, chlorohydrate, menthol, quinine sulfate, ure- thene... 

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